Bronchial asthma is a pathological symptom, in which airway is contracted by airway contraction and inflammation, causing paroxysmal cough, stridor, and breathing difficulty. The drugs for treatment of it include steroidal agents for inhalation, which have a strong antiinflammatory effect, P stimulants and theophyllines which are bronchodilating agents, antiallergic agents which inhibit the effect of chemical mediators, etc.
Histamine, leukotrienes, prostaglandins, TNF-α, etc. are known as various chemical mediators which are released from mast cells or basophils which are concerned in bronchial asthma. Among leukotrienes (LTs), cysteinyl leukotrienes (abbreviated cysLTs hereinafter) represented by LTC4, LTD4 and LTE4 have approximately 1000 times stronger contractile effect on airway as compared to histamine. Moreover, cysLTs promote induction of airway inflammation, typically inflammation cell invasion, airway hypersensitivity and mucus secretion in airway, and they are deeply involved in basic pathology of bronchial asthma.
The leukotriene receptor antagonists which are clinically used, e.g. pranlukast hydrate represented by the formula (A) (See Patent Document 1), montelukast sodium represented by the formula (B) (See Patent Document 2) and zafirlukast represented by the formula (C) (See Patent Document 3) are widely used as useful agents for the treatment of bronchial asthma and allergic rhinitis, which improves various kinds of symptoms and respiratory functions.

However, it is known these leukotriene receptor antagonists are more effective for mild or moderate symptoms than for severe symptoms. It is also known that there exist some non-responders with mild or moderate symptoms on whom the pharmaceutical agent does not have effect. So agents having higher efficacy than the existing agents have been desired.
Pranlukast hydrate has a strong antagonistic activity against leukotriene receptor, but it also has problems of physical property and systemic absorption.
It is known that a compound represented by the formula (D)

wherein all symbols have the same meanings as described in the document, has an antagonistic activity against cysLT2 receptor.
Pranlukast hydrate which is a leukotriene antagonist is useful for sinusitis (See Patent Document 5), headache such as migraine, migrainous neuralgia or tension-type headache (See Patent Document 6), endometriosis (See Patent Document 7), dysmenorrhea (See Patent Document 8), Meniere's disease, etc.
Patent Document 1: Japan Patent No. 1741466
Patent Document 2: Japan Patent No. 2501385
Patent Document 3: Japan Patent No. 1955810
Patent Document 4: WO2000/18399
Patent Document 5: JP-A-2004-168718
Patent Document 6: JP-A-2002-187855
Patent Document 7: WO2005/058878